Granulation of finely-divided materials in a wet state, with a view to their subsequent combustion



Apnl 16, 1963 A. A. J. QUINTIN 3,085,522

GRANULATION OF FINELY-DIVIDED MATERIALS IN A WET STATE, WITH A VIEW TO THEIR SUBSEQUENT COMBUSTION Filed June 29, 1960 2 Sheets-Sheet 1 iNVENTOR ALBERT ANDRE JOSEPH QUINTIN 4. W I BY I? 7/ ATroziusv April 16, 1963 A A. J. QUINTIN 3,085,522

GRANULATION OF FINELYDTVIDED MATERIALS IN A WET STATE, WITH A VIEW TO THEIR SUBSEQUENT COMBUSTION Filed June 29, 1960 2 Sheets-Sheet 2 FIG.2

11 INVENTOR ALBERT ANDRE I05 EPH QUINTIN United States Patent This invention relates to a process and plant for the granulation of finely-divided materials in a wet state, with a View to their subsequent combustion.

One of the objects of the invention is to obtain an economical combustion of pulverulent combustible matter in a wet state, and more particularly of combustible matter having a very low calorific power, such as sterile schlamms or shales rejected during treatment by flotation of coal fines in the washing plant of collieries. Such material is considered at present as being valueless and difficult to dump.

Another object of the invention is to obtain by the subsequent combustion or roasting a product in granular shape, which product may be easily dumped and is not carried away by the wind.

The invention consists in a furnace for the combustion of grains of material in a finely divided and wet state, having a chamber with a bed of material subjected to said combustion treatment and an atmosphere of gases, with a granulating device for the material arranged upon the roof of the furnace, a passage provided in the said roof allowing the grains of material to fall freely into the said chamber of furnace where they are dried and hardened by the combustion gases before they reach the bed of material in the furnace.

The invention affords an important saving in the cost of the plant with a considerable saving of heat.

The granulating device according to the present invention consists advantageously of a horizontal sieve through the perforations of which the wet material, brought in a state of a firm paste, is mechanically forced to pass, and the small cylinder of material which leave the perforations of the sieve are immediately fragmented to form grain-s which fall into the furnace. The wet material may of course be brought to a convenient percentage of moisture kneaded with addition if necessary of a binding material such as clay, for producing a paste of the right consistency which is fed to the granulating device.

The sieve may be placed immediately above an orifice of sufficient dimensions, provided in the masonry roof of the furnace, so that the production of the wet grains shall be effected immediately above the said orifice. The cylinders of extruded material hang thus freely and remain thus separated from one another, and the grains obtained by the fragmentation of the cylinders fall, as soon as they are formed, into the combustion chamber through the incadescent combustion gases without meeting any obstacle. They are superficially dried and hardened by the combustion gases before they reach the bed of material in combustion.

The apparatus for conditioning the charge of the furnace comprises advantageously a cylindrical shaft wherein the paste is fed, a perforated bottom and one or several inclined blades which rotate just above the said bottom and press the wet material through its perforations, whilst the cylinders which have been extruded through the said perforations, are immediately cut to the desired length by a device adapted to that purpose.

Use may advantageously be made according to the present invention of combustion furnaces for shales of coll-ieries, such as described in our patent applications "ice Ser. Nos. 751,550 and 779,725, which applications are now abandoned.

The fragmentation to the desired length of the cylinders issuing from the sieve may be obtained for instance by any of the following means (without however being restricted thereto):

(a) A rotating knife or wire placed immediately against the lower face of the perforated bottom of the granulating device. It may be driven by the vertical axis of the latter. The speed of the rotating knife or wire is such that the small extruded cylinders are cut to the desired length.

(b) A vibrator which is mounted upon a metal sleeve forming a shaft and supporting a perforated bottom, or which is fixed on the perforated bottom which is resiliently connected with the shaft. The vibrator transmits vibrations to the perforated bottom, which vibrations are directed in a horizontal plane, thus breaking the small cylinders which are extruded through the perforations of the sieve before they have been fragmented by their own weight. The amplitude and frequency of the vibrations fix the length of the grains.

(c) A vibrator transmits to the perforated bottom vertical vibrations of suitable amplitude and frequency, which vibrations cause the cylinders of material to break at the point where they leave the perforated bottom, before being fragmented by their own weight.

In the accompanying drawings,

FIGURE 1 is a vertical cross-section across a plant according to the invention.

FIGURES 2, 3 and 4 show details.

The apparatus as shown in FIGURE 1 of the drawings allows of obtaining with colliery schlamms or shales containing from 15 to 20% of water, an output of about 7 metrical tons per hour and per m. of surface of the perforated bottom, in the form of grains having a diameter of from 4 to 8 mm. and a length of from 5 to about 15 Referring to FIGURE 1 of the drawings, a motor 1 drives a change speed gear 2 which, through the intermediary of a pair of gears 3 and 4, drives a vertical axle 5 carrying inclined blades 10 and 10' and a knife 11.

The said vertical axle is held and supported by bearings 7 and 8 which are fixed upon the frame 15 which supports the entire structure through the intermediary of cross-members 16 and 17.

The reference numeral 9 shows a metal outer sleeve of the granulating device, forming a shaft which supports a perforated bottom 12.

The said shaft is fixed to the frame by means of bars, since in that type of construction the device which cuts the cylinders to the required length is the knife 11 and therefore, in that mode of construction, the shaft may be fixed.

The connection of the shaft with the roof 20 of the combustion chamber 19 is effected by means of a removable joint 14 fixed on the one side to the shaft and on the other side to a rim integral with the roof, by means of collars 13, which joint is gastight and resilient.

The reference numeral 18 shows diagrammatically the outlet of the gases from the combustion or roasting chamber, which gases lick the inner side of the roof on the outside of which the granulating device is situated.

FIGURE 2 shows a detail of the perforated bottom with a metal sleeve 9 forming a shaft, and also a perforated bottom 12 having a double wall for allowing cooling with water flowing through the free space 21.

iSllCh an arrangement can be more particularly used when the furnace is of the type in which the radiation of the combustion layer placed upon the perforated bottom of the granulating device, is excessive.

The two metal sheets forming the perforated bottom are interconnected by a certain number of cross-members 22 which are perforated as shown, to allow a passage for the wet material.

FIGURE 3 shows an arrangement of the vertical axle carrying two inclined blades and 10 which are diametrically opposed and inclined in the same manner relatively to the movement of the axle 5, and a knife 11 rotating underneath the perforated bottom and applied practically against it, so as to cut the small cylinders extruded through the perforations of the cross-members 22 under the effect of the pressure exerted upon the material by the rotation of the inclined blades 10 and 10'.

The frame carrying the entire structure of the driving mechanism for the vertical axle of the granulating device and of the shaft of the latter as shown in FIGURE 1, is mounted upon rollers 24 and may be displaced along a track 23. In this way, after one of the collars 13 has been removed, it is possible to remove away the entire structure by rolling, to replace it by a reserve group placed along the same track, and to place the said second group into operation after having closed the collar 13, with a view to continuing the feed of the furnace at the desired speed. Such an operation may be made very easily and very rapidly.

FIGURE 4 shows a fragmentation device for the cylinders extruded through the perforations of the sieve, which uses vibrations directed in a horizontal plane. The shaft of the granulating device is suspended to a frame 17 supporting the driving mechanism of the vertical axle, by means of three or four connecting rods permitting a horizontal vibration of the shaft to take place, the shaft being fixed to the connected rods with intermediary silent blocks.

In FIGURE 4, the members which are common to the device rotating knife shown in FIGURE 1, and to the device vibrator shown in FIGURE 4, are shown by the same reference numerals as those illustrating them in FIGURE 1.

The vibrator known per se fixed to the cylindrical shaft supporting the perforated bottom has been diagrammatically shown at 26, whilst 27-27 show the rods serving for suspension to the frame 17 which rods are inserted through a member 29 fixed to the outer sleeve 9 by means of lugs 30. Since the shaft in that case is no longer rigidly held relative to the frame, the rotation of the inclined blades 16-10 would have for its effect to produce a rotation of the shaft around the vertical axle if the said shaft were not held in position, and this is obtained by means of four chains 28-28 fixed to the vertical columns 15. The chains do not prevent vibrations of the shaft of the granulating device from taking place.

The fragmentation device may be a vibrating device generating vertical vibrations of the kind used with certain sieving plants. In that case, which is not illustrated in a special figure, the shaft 9 of FIGURES 1 and 4 is displaced vertically between three rollers arranged at from one another, under the effect of two eccentrics mounted upon a horizontal axle driven by the motor with change speed gear 1, 2 or by an auxiliary group.

The flexible connecting member 14 of FIGURES 1 and 4 is shaped so as to allow a small vertical displacement of the shaft.

What I claim is:

In a furnace adapted for the combustion of finely divided combustible materials initially in a wet pasty state and including a combustion chamber, means for feeding combustible material to said chamber located in the roof of the chamber, outlet means for removing combustion gas from said chamber, said feeding means including a granulating device comprising a cylindrical hollow container, a horizontally disposed sieve member forming the bottom of said container provided with passages for the downward movement of said pasty combustible material, said sieve having a cooling jacket surrounding said passages to permit access of a coolant, a vertical shaft extending through said container, said shaft having mounted thereon and extending outward therefrom immediately above said sieve, a pair of inclined blades diametrically opposed and inclined in the same manner relative to the movement of said shaft to cause said pasty material to traverse the sieve passages, and a blade member mounted on said shaft immediately below said sieve and extending outward therefrom to cut off extruded paste portions, means for rotating said shaft and vibrating means mounted on said container to produce horizontal vibration of said container and sieve to aid in the passage of the pasty material therethrough.

References Cited in the file of this patent UNITED STATES PATENTS 925,400 Trump June 15, 1909 1,554,780 Berigan et al Sept. 22, 1925 2,029,725 Kuhner Feb. 4, 1936 2,433,684 Damond Dec. 30, 1947 2,483,728 Glaeser Oct. 4, .1949 2,583,862 Lichtenstein Jan. 29, 1952 2,614,290 Street Oct. 21. 1952 2,744,477 Hartley May 8, 1956 2,931,067 Delaloye et al Apr. 5, 1960 FOREIGN PATENTS 1,590 Great Britain 1865 229,711 Great Britain Feb. 26, 1925 

